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channel speaker should be located centered on the TV screen—to keep center channel
sound coming from the center of the screen..
Balance adjustment can compensate for some physical location difference between left
and right. Time-delay adjustment of surround sound can compensate for some physical
location difference between front and rear. With mono signals equidistant, symmetrical
location is still desired to minimize balancing requirements. Proximity to additional side
wall, ceiling or floor surfaces will cause increases and decreases in frequency response
which are very difficult to electronically equalize for smooth response overall—particularly
when only some of the speakers are affected.
Ceiling locations are generally good locations, particularly for rear channel and secondary
listening, allowing symmetrical layouts and the increased volume between floor joists for
improved bass response. Some sound output will transmit through the wall behind (or
floor above) a speaker; and, while this can be lessened with insulation and other
installation techniques, it should be considered in finalizing locations.
All CustomSound models are designed to maintain the same tonal balance when different
models are mixed in a system. The same model should be used in symmetrical listening
locations in a system—front left and front right; rear left and rear right.
Each CustomSound speaker carton contains a full-size template of the front of the
speaker. These templates can be used when initially locating speakers and then when
marking and cutting out speaker locations. We encourage temporarily taping templates in
the intended locations and then sitting in the primary listening location and considering the
above guidelines again—also realizing that behind-the-wall conflicts will probably require
some adjustment to the intended locations before they are final.
C. System and Supply
Typically, a cable with a wire pair must connect every speaker to the sources. This
amplified and controlled source supply may go directly from a power amplifier or through
a local, supplemental volume control. In some, mono-only systems, a single wire may
"daisy chain", entering and exiting from one speaker to another—beginning and ending at
the amplifier.
Overall, a musical source—audio or video—is fed first through a preamplifier with
switching and tone controls—and then through a power amplifier and onwards to each
speaker. The preamplifier provides a level of tone controls—bass, treble, and balance left
to right. Surround processors, operating between the preamplifier and amplifier stages,
can provide surround decoding and another level of channel balancing—front left, right,
and center; surround left and right; and subwoofer. An equalizer before the amplifier can
provide some adjustment to smooth response for field conditions and preferences.
Multiple amplifiers may be used for multiple zones and speaker loads.
D. Obstructions
With tentative speaker locations determined, potential obstructions must be explored and
the conflicts resolved: Structural; Mechanical—Electrical, Plumbing, and HVAC; and
Furnishings.
Temporarily mark and view tentative speaker locations and the existing construction
carefully to determine the existing structure and mechanical installations and potential
obstructions. Adjust the speaker layout, the furnishings, the mechanical, and/or the
structural to resolve the conflicts. Layout, review, and resolution on building plans can be
a very efficient process. However, some conflicts will inevitably appear and need to be
resolved as actual conditions are reviewed and as installation proceeds.
Most typically and very basically, residential walls are constructed of wooden
studs—nominally 2" x 4", but measuring 1½” x 3½" (sometimes, particularly on exterior
walls 2" x 6", measuring 1½" x 5½") and normally located on 16" centers—with 14½"
between studs. This stud pattern usually begins from one, exterior corner and results in a
smaller than normal spacing at the other corner. The full height "common" studs extend
from a flat "sole" plate on the floor to a "top" plate (often doubled) at the top of the wall.
Top headers of doubled 2" x 4"s (or larger) are placed on edge spanning over doorways
and windows, and doubled sill headers run under window openings. "Trimmer/jack" partial
studs run under the ends of all headers, doubled against full studs against the ends of all
headers. Shorter partial "cripple" studs run over headers to the top plate and under sills to
the bottom plate—at nominal spacing. Blocking may be between studs about mid-wall,
behind cabinets and other fixtures mounted to the wall, and over and under ductwork
through the stud cavity. Electrical receptacles and switches are mounted in electrical
boxes, usually mounted to a stud. Removing electrical cover plates in finished walls is a
good initial step to determine where studs are located.
Floors typically are constructed of wooden joists—nominally 2" x 8" or deeper, but
measuring 1½" x 7¼" or deeper and normally located on 16" centers (but not uncommonly
on 12" centers). Roofs typically are constructed of wooden rafters—nominally 2" x 6" or
deeper, but measuring 1½" x 5½” and located on 16" centers (but not uncommonly on 24"
centers). Ceilings are usually backed by 1" x 3" strapping leveled beneath the floor joists
or roof rafters and located on 16" centers.
Electrical cables run to, and most often from, all electrical boxes—which are grouped on
circuits. Plumbing supply, drain and vent lines run to and from all plumbing fixtures—which
are grouped on vertical risers. Heating supply lines circulate through radiation
fixtures—which are grouped in zones off vertical risers. HVAC ductwork runs to all supply
grills and from all return grills. Control wiring (sometimes tubing) runs to all controls.
Corner bay locations should be avoided since at least one corner bay is usually smaller
than normal, which will decrease bass response, and closeness to the side wall will cause
some unevenness in frequency response. Mechanical activity that occupies volume in the
speaker wall cavity will decrease bass response and may transmit sound to other,
unintended areas. Electrical power wiring should not run close to the speaker or it's audio
supply; crossing away from the speaker and its supply has minimal effect.
E. Weather Resistance
CustomSound speakers are designed for outstanding durability as well as outstanding
sonic performance. Polypropylene cones with rubber surrounds, stainless steel fasteners,
aluminum grills, and ABS plastic frames with UV resistance increase the range of locations
where CustomSound speakers can continue to satisfy. It should be remembered that
nothing is fully weatherproof (or soundproof or fireproof). Salt water, driving rains, direct
sunlight, and freeze and thaw cycles will degrade all materials—even granite—over time.
Almost any interior locations other than submerged, baked, or frozen are fine. Good
exterior locations provide some protection from the weather, and these are usually also
better locations for improved sonic performance. Porch ceilings and walls are fine. On
exterior walls, some weather shelter is desirable—under overhanging eaves is fine. Totally
exposed, unsheltered locations will not sound as good and will deteriorate over time.
F. Tricks of the Trades—Nothing's Plumb, Square, or True
All people in construction realize that it is an exacting but inexact craft—nothing is exactly,
absolutely plumb, square, or true. The craft is to understand and respect the tolerances of
materials, tools, makers, and users—what will look right to the eye, is reasonably possible
to build, and will retain it's position over years—within the budgets of money and time.
Planning, measuring, and coordinating are important; but conflicts, tradeoffs, and
imperfections are inevitable in the final construction. Pre-construction drawings are very
